What caliber, what game and farthest range?
I started with and used "Bullet Flight", but ended up getting a custom turret. All I have to do is use my laser range finder to range the game then turn the turret to the yardage, hold for wind and shoot. It makes it very easy while in hunting situations.

i have a 338 edge nightforce on top for hunting 800 , 900 yards would be my max range . but for shooting a mile is fun exbal sounds good i have a ipag pocket pda will this work well? as for ballistic turrent i have a 300 rum with a swarovski z6 with ballistic turrent its nice

I don't see any place to have one custom made, looks precanned for the 308, 300Win and 338 Lapua. I don't know about that even if you could get one made, no animal stands in 50yrd increments and 1000yrds isn't going to cut it. Don't see on replacing a ballistics program in a LRH situation.